利用微信公众号提供的素材存储当免费图床用

<?php

// 返回JSON
header("Content-type:application/json");
// 允许上传的图片后缀
$allowedExts = array("jpeg", "jpg", "png");
// 后缀名
if ($allowedExts[0] == 'jpeg') {
    $hzm = 'jpg';
}else{
    $hzm = $allowedExts[0];
}
// 获取选择的文件
$temp = explode(".", $_FILES["file"]["name"]);
// 获取文件后缀名
$extension = end($temp);

if ((($_FILES["file"]["type"] == "image/gif")
|| ($_FILES["file"]["type"] == "image/jpeg")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/pjpeg")
|| ($_FILES["file"]["type"] == "image/x-png")
|| ($_FILES["file"]["type"] == "image/png"))
&& ($_FILES["file"]["size"] < 10485760)
&& in_array($extension, $allowedExts)){
    if ($_FILES["file"]["error"] > 0){
        $result = array(
            'code' => 201,
            'msg' => '上传失败'.$_FILES["file"]["error"]
        );
    }else{
        // 重命名
           $new_file = date("Y-m-d")."-".rand(10000,99999).".".$hzm;
           // 上传到自己的服务器
        move_uploaded_file($_FILES["file"]["tmp_name"], "upload/".$new_file);
        // 获取真实地址
        $filepath = realpath(dirname(__FILE__));
        $upload_filepath = $filepath."/upload/".$new_file;
        // 上传到微信服务器
        $imgurl = upload_img($upload_filepath);
        // 验证上传结果
        if(strpos($imgurl,'http') !== false){

            // 上传成功
            $result = array(
                'code' => 200,
                'msg' => '上传成功',
                'url' => $imgurl
            );
            // 删除本地素材
            unlink($upload_filepath);
        }else{

            // 上传失败
            $result = array(
                'code' => 202,
                'msg' => '上传失败'
            );
        }
    }
}

// 获取access_token
function getToken(){
    // appid和secret
    $appid='填写你公众号的appid';
    $appsecret='填写你公众号的appsecret';
    // 读取access_token
    include './access_token.php';
    // 判断是否过期
    if (time() > $access_token['expires']){
        // 如果已经过期就得重新获取并缓存
        $access_token = array();
        $access_token['access_token'] = getNewToken($appid,$appsecret);
        $access_token['expires']=time()+7000;
        // 将数组写入php文件
        $arr = '<?php'.PHP_EOL.'$access_token = '.var_export($access_token,true).';'.PHP_EOL.'?>';
        $arrfile = fopen("./access_token.php","w");
        fwrite($arrfile,$arr);
        fclose($arrfile);
        // 返回当前的access_token
        return $access_token['access_token'];
    }else{
        // 如果没有过期就直接读取缓存文件
        return $access_token['access_token'];
    }
}
// 获取新的access_token
function getNewToken($appid,$appsecret){
    $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={$appid}&secret={$appsecret}";
    $access_token_Arr =  https_request($url);
    return $access_token_Arr['access_token'];
}
// curl请求函数
function https_request ($url){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    $out = curl_exec($ch);
    curl_close($ch);
    return  json_decode($out,true);
}
// 上传图片素材到微信服务器
function upload_img($realpath){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, 'https://api.weixin.qq.com/cgi-bin/material/add_material?access_token='.getToken().'&type=image');
    $data = array(
        'media' => new CURLFile($realpath)
    );
    curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $upimg = curl_exec($ch);
    return json_decode($upimg)->url;
    curl_close($ch);
}

// 返回JSON对象
echo json_encode($result,JSON_UNESCAPED_UNICODE);
?>

{"media_id":"8IZhZUPXxsG_omeA5giO5By8VyHnjk7_oy0Co9jVWwxpgm-sqhx_Hkz_9rLVF9Ws","url":"http:\/\/mmbiz.qpic.cn\/mmbiz_png\/5zLSKyuEW2Kt5ZGZg7XUx05QyGOVFCpHqKic74qQP4gxzQJYXjwN4aGEiadtfUXax4fCXXV5ia1UnvSwdqxuqLCqA\/0?wx_fmt=png","item":[]}